I posted the text below in the Google webmaster forum and got no answer!
I think at the beginning of a day you should know in which direction you should steer your work, right?

I hope now that I get a valuable answer here. Many thanks in advance.

Eric

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"I have over 40 customer websites, all of which I created and optimized myself.
Since everyone knows that the performance values are an important criterion for the Google Ranking, I always invested a lot of time.

Meanwhile the setup of my pages is so good that I always reached 100/100 in the Google Pagespeed Insights Test (PSI). On GT Metrix 99%.

Now, however, the usual PSI link has been used to carry out another test recently, namely with Lighthouse.
With this test, suddenly none of my pages comes over 45% (aarrrgg).

The curiosity is that I get three different results.
1. via the already mentioned link to /speed/pagespeed/insights = 45%.
2. with the DEV-Tool in the Googlebrowser via Audits (also Lighthouse) = 68%.
3. via the PSI extension in the browser = still 100/100

My question is therefore quite simple:
WHICH OF THE THREE TEST OPTIONS IS THE ONE THAT WILL HAVE TO GUIDE ME IN THE FUTURE?
After all, one of the three must serve as the basis for the ranking!

By the way, I tested 20 of my 40 pages with all three Google tools and the results were identical different.

I'd be happy to wait for the answer if this still has to be researched internally at Google.
Besides me, many of my web designer colleagues are waiting for this answer,
because we're all completely insecure."
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